NEW PRODUCT Garden Highlights Coarse Pumice 5 litre SKU: 347570 MODEL: GHPC05 Error. try again later You've successfully joined the club $ 5 .99 each Mitre 10 Variants A washed, screened and graded pumice produced as a by-product of sand processing. This product is predominantly used in potting mixes to achieve a desirable air filled porosity and provide good drainage. Features and benefits Washed and screened. For sterile growing and improved drainage.